Supplement: Metalloendocrinology: Mapping Bioinorganic Chemistry in the Extracellular Space

项目摘要 铜是生物中必不可少的微量营养素，在呼吸和呼吸等过程中发挥着重要作用。 抗氧化剂防御。铜离子所处的环境对其活性至关重要，而它的 错区划分和不平衡与一系列疾病有关。虽然技术已经 为了研究细胞内的铜动态，细胞外的铜库相对较低- 特色化的。这项补充的父母拨款旨在阐明细胞外金属的形态。 空间，重点是金属与细胞外环境中另一个动态成分的相互作用， 荷尔蒙。本课题的主要研究对象是一种具有激素样功能的多肽--C-肽。 多肽，一种源于胰岛素原蛋白的31聚体。历史上被低估为无辜的次要标志 对于胰岛素，C肽因其独立于胰岛素的生物活性而受到越来越多的关注。然而，它的先进性 由于缺乏机械性的理解而受到阻碍。父项目下的工作表明，C- 多肽可以直接与铜结合，这是一种可以调节C肽活性的事件。在本提案的目标1中，我们 寻求确定C-肽及其截短体是否以及如何影响铜贩运。前期工作 表明金属结合的相互作用可以改变金属的动态平衡。中的组合 体外和体内的工作将寻求分析驱动C肽和铜之间相互作用的途径。 目的2试图利用铜和C-肽的相互作用来识别质膜受体 多肽。虽然孤儿GPCRGPR146被提议作为C-肽的合作伙伴，但这一说法仍然存在 辩论过了。我们假设金属与富含负电荷残基的多肽相互作用， 可能对受体识别有影响。这个目标将筛选C-肽与孤儿文库的相互作用 在存在和不存在过渡金属的情况下确定金属是否为受体所必需的GPCRS 识别，如果是的话，识别多肽的同源受体。为了实现这些研究目标，候选人 将在本补充材料的支持下，通过多方面的指导团队进行跨学科培训 金属内分泌过程的分子洞察。

PROJECT ABSTRACT Copper is an essential micronutrient in biology, playing fundamental roles in processes such as respiration and antioxidant defense. The context in which a copper ion resides is vital to its activity, and its miscompartmentalization and imbalances is associated with a host of disorders. While technologies have emerged to investigate intracellular copper dynamics, the extracellular copper pool is relatively under- characterized. The parent grant of this supplement seeks to elucidate the speciation of metals in the extracellular space, with a focus on the interplay of metals with another dynamic component in the extracellular environment, hormones. The main research of this objective focuses on a particular peptide with hormone-like functions, C- peptide, a 31-mer derived from the proinsulin protein. Historically undervalued as an innocent secondary marker for insulin, C-peptide is of increasing interest for its bioactivity independent of insulin. However, its advancement has been hampred by lack of mechanistic understanding. Work under the parent project has shown that C- peptide can directly bind to copper, an event that can modulate C-peptide's activity. In Aim 1 of this proposal, we seek to determine whether and how C-peptide and its truncates affect copper trafficking. Preliminary work suggests that the metal-binding interaction can shift the homeostatic balance of the metal. A combination of in vitro and in vivo work will seek to analyze the pathways that drive the interplay between C-peptide and copper. Aim 2 seeks to leverage the interactions of copper and C-peptide to identify a plasma membrane receptor for the peptide. While an orphan GPCR, GPR146, has been proposed as a partner for C-peptide, this claim remains debated. We hypothesize that metal interactions with the peptide, which is rich in negatively-charged residues, may be influential in receptor recognition. This aim will screen for C-peptide interactions with a library of orphan GPCRs in the presence and absence of transition metals to determine whether metals are integral to receptor recognition, and if so, identify a cognate receptor for the peptide. To achieve these research goals, the candidate to be supported by this supplement will be trained across disciplines with a multifaceted mentoring team to bring molecular insight to metalloendocrinological processes.